xref: /openbmc/u-boot/arch/arm/mach-mvebu/dram.c (revision e246b728)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2009
4  * Marvell Semiconductor <www.marvell.com>
5  * Written-by: Prafulla Wadaskar <prafulla@marvell.com>
6  */
7 
8 #include <config.h>
9 #include <common.h>
10 #include <asm/io.h>
11 #include <asm/arch/cpu.h>
12 #include <asm/arch/soc.h>
13 
14 #if defined(CONFIG_ARCH_MVEBU)
15 /* Use common XOR definitions for A3x and AXP */
16 #include "../../../drivers/ddr/marvell/axp/xor.h"
17 #include "../../../drivers/ddr/marvell/axp/xor_regs.h"
18 #endif
19 
20 DECLARE_GLOBAL_DATA_PTR;
21 
22 struct sdram_bank {
23 	u32	win_bar;
24 	u32	win_sz;
25 };
26 
27 struct sdram_addr_dec {
28 	struct sdram_bank sdram_bank[4];
29 };
30 
31 #define REG_CPUCS_WIN_ENABLE		(1 << 0)
32 #define REG_CPUCS_WIN_WR_PROTECT	(1 << 1)
33 #define REG_CPUCS_WIN_WIN0_CS(x)	(((x) & 0x3) << 2)
34 #define REG_CPUCS_WIN_SIZE(x)		(((x) & 0xff) << 24)
35 
36 #ifndef MVEBU_SDRAM_SIZE_MAX
37 #define MVEBU_SDRAM_SIZE_MAX		0xc0000000
38 #endif
39 
40 #define SCRUB_MAGIC		0xbeefdead
41 
42 #define SCRB_XOR_UNIT		0
43 #define SCRB_XOR_CHAN		1
44 #define SCRB_XOR_WIN		0
45 
46 #define XEBARX_BASE_OFFS	16
47 
48 /*
49  * mvebu_sdram_bar - reads SDRAM Base Address Register
50  */
51 u32 mvebu_sdram_bar(enum memory_bank bank)
52 {
53 	struct sdram_addr_dec *base =
54 		(struct sdram_addr_dec *)MVEBU_SDRAM_BASE;
55 	u32 result = 0;
56 	u32 enable = 0x01 & readl(&base->sdram_bank[bank].win_sz);
57 
58 	if ((!enable) || (bank > BANK3))
59 		return 0;
60 
61 	result = readl(&base->sdram_bank[bank].win_bar);
62 	return result;
63 }
64 
65 /*
66  * mvebu_sdram_bs_set - writes SDRAM Bank size
67  */
68 static void mvebu_sdram_bs_set(enum memory_bank bank, u32 size)
69 {
70 	struct sdram_addr_dec *base =
71 		(struct sdram_addr_dec *)MVEBU_SDRAM_BASE;
72 	/* Read current register value */
73 	u32 reg = readl(&base->sdram_bank[bank].win_sz);
74 
75 	/* Clear window size */
76 	reg &= ~REG_CPUCS_WIN_SIZE(0xFF);
77 
78 	/* Set new window size */
79 	reg |= REG_CPUCS_WIN_SIZE((size - 1) >> 24);
80 
81 	writel(reg, &base->sdram_bank[bank].win_sz);
82 }
83 
84 /*
85  * mvebu_sdram_bs - reads SDRAM Bank size
86  */
87 u32 mvebu_sdram_bs(enum memory_bank bank)
88 {
89 	struct sdram_addr_dec *base =
90 		(struct sdram_addr_dec *)MVEBU_SDRAM_BASE;
91 	u32 result = 0;
92 	u32 enable = 0x01 & readl(&base->sdram_bank[bank].win_sz);
93 
94 	if ((!enable) || (bank > BANK3))
95 		return 0;
96 	result = 0xff000000 & readl(&base->sdram_bank[bank].win_sz);
97 	result += 0x01000000;
98 	return result;
99 }
100 
101 void mvebu_sdram_size_adjust(enum memory_bank bank)
102 {
103 	u32 size;
104 
105 	/* probe currently equipped RAM size */
106 	size = get_ram_size((void *)mvebu_sdram_bar(bank),
107 			    mvebu_sdram_bs(bank));
108 
109 	/* adjust SDRAM window size accordingly */
110 	mvebu_sdram_bs_set(bank, size);
111 }
112 
113 #if defined(CONFIG_ARCH_MVEBU)
114 static u32 xor_ctrl_save;
115 static u32 xor_base_save;
116 static u32 xor_mask_save;
117 
118 static void mv_xor_init2(u32 cs)
119 {
120 	u32 reg, base, size, base2;
121 	u32 bank_attr[4] = { 0xe00, 0xd00, 0xb00, 0x700 };
122 
123 	xor_ctrl_save = reg_read(XOR_WINDOW_CTRL_REG(SCRB_XOR_UNIT,
124 						     SCRB_XOR_CHAN));
125 	xor_base_save = reg_read(XOR_BASE_ADDR_REG(SCRB_XOR_UNIT,
126 						   SCRB_XOR_WIN));
127 	xor_mask_save = reg_read(XOR_SIZE_MASK_REG(SCRB_XOR_UNIT,
128 						   SCRB_XOR_WIN));
129 
130 	/* Enable Window x for each CS */
131 	reg = 0x1;
132 	reg |= (0x3 << 16);
133 	reg_write(XOR_WINDOW_CTRL_REG(SCRB_XOR_UNIT, SCRB_XOR_CHAN), reg);
134 
135 	base = 0;
136 	size = mvebu_sdram_bs(cs) - 1;
137 	if (size) {
138 		base2 = ((base / (64 << 10)) << XEBARX_BASE_OFFS) |
139 			bank_attr[cs];
140 		reg_write(XOR_BASE_ADDR_REG(SCRB_XOR_UNIT, SCRB_XOR_WIN),
141 			  base2);
142 
143 		base += size + 1;
144 		size = (size / (64 << 10)) << 16;
145 		/* Window x - size - 256 MB */
146 		reg_write(XOR_SIZE_MASK_REG(SCRB_XOR_UNIT, SCRB_XOR_WIN), size);
147 	}
148 
149 	mv_xor_hal_init(0);
150 
151 	return;
152 }
153 
154 static void mv_xor_finish2(void)
155 {
156 	reg_write(XOR_WINDOW_CTRL_REG(SCRB_XOR_UNIT, SCRB_XOR_CHAN),
157 		  xor_ctrl_save);
158 	reg_write(XOR_BASE_ADDR_REG(SCRB_XOR_UNIT, SCRB_XOR_WIN),
159 		  xor_base_save);
160 	reg_write(XOR_SIZE_MASK_REG(SCRB_XOR_UNIT, SCRB_XOR_WIN),
161 		  xor_mask_save);
162 }
163 
164 static void dram_ecc_scrubbing(void)
165 {
166 	int cs;
167 	u32 size, temp;
168 	u32 total_mem = 0;
169 	u64 total;
170 	u32 start_addr;
171 
172 	/*
173 	 * The DDR training code from the bin_hdr / SPL already
174 	 * scrubbed the DDR till 0x1000000. And the main U-Boot
175 	 * is loaded to an address < 0x1000000. So we need to
176 	 * skip this range to not re-scrub this area again.
177 	 */
178 	temp = reg_read(REG_SDRAM_CONFIG_ADDR);
179 	temp |= (1 << REG_SDRAM_CONFIG_IERR_OFFS);
180 	reg_write(REG_SDRAM_CONFIG_ADDR, temp);
181 
182 	for (cs = 0; cs < CONFIG_NR_DRAM_BANKS; cs++) {
183 		size = mvebu_sdram_bs(cs);
184 		if (size == 0)
185 			continue;
186 
187 		total = (u64)size;
188 		total_mem += (u32)(total / (1 << 30));
189 		start_addr = 0;
190 		mv_xor_init2(cs);
191 
192 		/* Skip first 16 MiB */
193 		if (0 == cs) {
194 			start_addr = 0x1000000;
195 			size -= start_addr;
196 		}
197 
198 		mv_xor_mem_init(SCRB_XOR_CHAN, start_addr, size - 1,
199 				SCRUB_MAGIC, SCRUB_MAGIC);
200 
201 		/* Wait for previous transfer completion */
202 		while (mv_xor_state_get(SCRB_XOR_CHAN) != MV_IDLE)
203 			;
204 
205 		mv_xor_finish2();
206 	}
207 
208 	temp = reg_read(REG_SDRAM_CONFIG_ADDR);
209 	temp &= ~(1 << REG_SDRAM_CONFIG_IERR_OFFS);
210 	reg_write(REG_SDRAM_CONFIG_ADDR, temp);
211 }
212 
213 static int ecc_enabled(void)
214 {
215 	if (reg_read(REG_SDRAM_CONFIG_ADDR) & (1 << REG_SDRAM_CONFIG_ECC_OFFS))
216 		return 1;
217 
218 	return 0;
219 }
220 
221 /* Return the width of the DRAM bus, or 0 for unknown. */
222 static int bus_width(void)
223 {
224 	int full_width = 0;
225 
226 	if (reg_read(REG_SDRAM_CONFIG_ADDR) & (1 << REG_SDRAM_CONFIG_WIDTH_OFFS))
227 		full_width = 1;
228 
229 	switch (mvebu_soc_family()) {
230 	case MVEBU_SOC_AXP:
231 	    return full_width ? 64 : 32;
232 	    break;
233 	case MVEBU_SOC_A375:
234 	case MVEBU_SOC_A38X:
235 	case MVEBU_SOC_MSYS:
236 	    return full_width ? 32 : 16;
237 	default:
238 	    return 0;
239 	}
240 }
241 
242 static int cycle_mode(void)
243 {
244 	int val = reg_read(REG_DUNIT_CTRL_LOW_ADDR);
245 
246 	return (val >> REG_DUNIT_CTRL_LOW_2T_OFFS) & REG_DUNIT_CTRL_LOW_2T_MASK;
247 }
248 
249 #else
250 static void dram_ecc_scrubbing(void)
251 {
252 }
253 
254 static int ecc_enabled(void)
255 {
256 	return 0;
257 }
258 #endif
259 
260 int dram_init(void)
261 {
262 	u64 size = 0;
263 	int i;
264 
265 	for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
266 		/*
267 		 * It is assumed that all memory banks are consecutive
268 		 * and without gaps.
269 		 * If the gap is found, ram_size will be reported for
270 		 * consecutive memory only
271 		 */
272 		if (mvebu_sdram_bar(i) != size)
273 			break;
274 
275 		/*
276 		 * Don't report more than 3GiB of SDRAM, otherwise there is no
277 		 * address space left for the internal registers etc.
278 		 */
279 		size += mvebu_sdram_bs(i);
280 		if (size > MVEBU_SDRAM_SIZE_MAX)
281 			size = MVEBU_SDRAM_SIZE_MAX;
282 	}
283 
284 	for (; i < CONFIG_NR_DRAM_BANKS; i++) {
285 		/* If above loop terminated prematurely, we need to set
286 		 * remaining banks' start address & size as 0. Otherwise other
287 		 * u-boot functions and Linux kernel gets wrong values which
288 		 * could result in crash */
289 		gd->bd->bi_dram[i].start = 0;
290 		gd->bd->bi_dram[i].size = 0;
291 	}
292 
293 
294 	if (ecc_enabled())
295 		dram_ecc_scrubbing();
296 
297 	gd->ram_size = size;
298 
299 	return 0;
300 }
301 
302 /*
303  * If this function is not defined here,
304  * board.c alters dram bank zero configuration defined above.
305  */
306 int dram_init_banksize(void)
307 {
308 	u64 size = 0;
309 	int i;
310 
311 	for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
312 		gd->bd->bi_dram[i].start = mvebu_sdram_bar(i);
313 		gd->bd->bi_dram[i].size = mvebu_sdram_bs(i);
314 
315 		/* Clip the banksize to 1GiB if it exceeds the max size */
316 		size += gd->bd->bi_dram[i].size;
317 		if (size > MVEBU_SDRAM_SIZE_MAX)
318 			mvebu_sdram_bs_set(i, 0x40000000);
319 	}
320 
321 	return 0;
322 }
323 
324 #if defined(CONFIG_ARCH_MVEBU)
325 void board_add_ram_info(int use_default)
326 {
327 	struct sar_freq_modes sar_freq;
328 	int mode;
329 	int width;
330 
331 	get_sar_freq(&sar_freq);
332 	printf(" (%d MHz, ", sar_freq.d_clk);
333 
334 	width = bus_width();
335 	if (width)
336 		printf("%d-bit, ", width);
337 
338 	mode = cycle_mode();
339 	/* Mode 0 = Single cycle
340 	 * Mode 1 = Two cycles   (2T)
341 	 * Mode 2 = Three cycles (3T)
342 	 */
343 	if (mode == 1)
344 		printf("2T, ");
345 	if (mode == 2)
346 		printf("3T, ");
347 
348 	if (ecc_enabled())
349 		printf("ECC");
350 	else
351 		printf("ECC not");
352 	printf(" enabled)");
353 }
354 #endif
355